[Gambas-user] gb3: DrawAlpha

Benoît Minisini gambas at ...1...
Tue Jul 5 12:34:19 CEST 2011

> Since DrawImage just copies the RGBA channels and PaintImage blends the
> channels using the alpha channel, I'm assuming that DrawAlpha copies
> (but does not blend) the alpha channel. Is that the case?

Actually DrawAlpha is PaintAlpha. I saw no point of just copying the alpha 

Blending the alpha channel is just keeping the greater transparency between 
the destination pixel and the source pixel. This is what DrawAlpha does.

By the way, I have fixed a bug in the alpha blending of PaintImage in revision 
#3926. Tell me if you notice the change.


Benoît Minisini

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